stop_activity

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the behavioral burden. It reveals the ambiguity-resolution rule for type_name and the backdating options, but does not state side effects (e.g., whether this ends the interval permanently), permissions, or error behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, front-loaded with the core action, no filler. Every clause adds operational insight.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given 5 parameters fully documented in the schema and the absence of an output schema, the description covers the main action, backdating, and the conditional type_name behavior. It is sufficient for correct invocation, though it leaves edge-case behavior (multiple active activities without type_name) implicit.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3. The description adds value by linking `at` and `stopped_minutes_ago` as alternative backdating methods and clarifying when type_name is optional, which goes beyond the schema descriptions.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description specifies the action ('Stop') on the resource ('activity') and extends to both running and paused states, clearly differentiating from siblings like pause_resume_activity or start_activity. The verb and resource are specific and unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

It provides context that type_name can be omitted when exactly one activity is active, guiding conditional parameter handling, but does not explicitly compare to pause_resume_activity or log_interval, so exclusions are implied rather than stated.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.